Вправи: 93

93. Спростіть вираз:

1) a+ 7\312 + a-4\49 = 3a+7+4(a-4)36 = 3a+21+4a-1636 = 7a+536;

2) 2b-7c\56 – 3b+2c\215 = 52b-7c-2(3b+2c)30 = 10b-35c-6b-4c30 = 4b-39c30;

3) 3x- 2\yx – 3y- 1\xy = y3x-2- x(3y-1)xy = 3xy-2y-3xy+ xxy = x-2yxy;

4) 6p+ 1\3p – 2p+ 8\1 3p = 36p+1-(2p+8)3p = 18p+3-2p-83p = 16p-53p;

5) 5m-n\1 14m – m-6n\27m = 5m- n-2(m-6n)14m = 5m- n-2m+12n14m = 3m+11n14m;

6) x+ 4\y11x – y-3\x 11y = yx+4-x(y-3)11xy = xy+4y- xy+3x11xy = 4y+3x11xy;

7) a+ b\cab + a-c\b ac = ca+ b+ b(a- c)abc = ac+ bc+ ab- bcabc = ac+ ababc;

8) k+4\k k – 3k- 4\1k2 = kk+4+(3k-4)k2 = k2+4k+3k-4k2 = k2+7k-4 k2;

9) x-y\y x3 – y-x2\xx2y = yx- y-x(y- x2)x3y = yx- y2-xy+ x3x3y = x3-y2 x3y;

10) c+ d\c2cd4 – c2-8d\dc3d3 = c2c+ d- d(c2-8d)c3d4 = c3+c2d- dc2+8d2c3d4 = c3+8d2c3d4.